Bending machine



G. R. GOIN BENDING MACHINE Jan. 3, 1939.

4 Sheets-Sheet 1 Filed March 27, 1935 mm N s m on. W M .A R w a, 6

Jan. 3 R. GON

BENDING MACHINE Filed March 27, 1935 4 Sheets-Sheet 2 I INVENTOR AT'l ORNg Jan. 3, 1939. e. R. GOIN 2,142,443

BENDING MACHINE Filed March 27, 1955 4 SheetS-Sheet 5 ATTOR Y G. R. GOIN BENDING MACHINE Jan. 3, 1939.

Filed March 2'7, 1935 4 Sheets-Sheet 4 INVENTOR a A. 6017? ATTORNE Patented Jan. 3, 1939 BENDING MACHINE George R; Goin, Detroit, Mich, asaignor to Peninsular Metal Products Corporation, a corporation oi Michigan Application March 2'1, 1935, Serial No. 13,214 24' Claims. (01. 153-32) This invention relates to bending machines and particularly to machines for bending substantially straight metal strips, of tubular or any other cross section, to a desired annular or other form.

The term annu1ar", as herein used, designates any member forming a closed or approximately closed loop, whether circular or of other form.

An object of the invention is to provide a fixed forming plate having an edge of the contour to be imparted to the work, and to provide for actuation around said edge, of a .carriage which mounts mechanism for pressing the work against said edge.

Another object is to adapt the last mentioned mechanism to yieldably hold the work against the forming plate, pneumatically or otherwise, under regulable pressure.

A further object is to adapt said carriage to be motor driven and to permit, by a comparatively simple mechanism, the bending operation to be performed under a powerfulleverage, minimizing the required motive power.

A further object is to provide an improved device for maintaining a fixed position of the end portion of the work initially applied to the forming plate, said device providing for a quick clamping and unclamping of such end portion.

A further object is to provide an improved bending mandrel for insertion in work of slotted tubular form and holding such work against the forming plate, and to mount such mandrel in a suitable holder on said carriage.

A further object is to assemble a propelling mechanism for said carriage upon a second carriage, and to effect an articulated drive connection between the two carriages facilitating travel around curves of short radius.

These and various other objects the invention attains by the construction hereinafter described, and illustrated in the accompanying drawings, wherein:

Fig. l is a top plan view of the machine, showing a length of molding partially bent to the form of a frame for a motor vehicle window.

Fig. 2 is a fragmentary vertical sectional view of the machine, particularly showing the carriage, its guide means and mechanism on the carriage for applying a bendingstress to the work, the section being taken on the line 2-2 of Fig. 1.

Fig. 3 is a vertical sectional view, taken upon the line '3-3 of Fig. 1, and particularly showing the propelling unit for the carriage and its articulated connection to the carriage.

Fig. 4 is a cross sectional view of the machine, taken on the line 4-4 of Fig. 1.

Fig. 5 is a horizontal section taken on the line I-! of Fig. 3, and primarily showing a carriage and driving means therefor.

Fig. 6 is a fragmentary vertical section taken on the line li6 of Fig. 1, and particularly showing a clamp for securing an end portion of a molding strip, preliminary to a bending operation.

Fig. 7 is a horizontal sectional view of thesame, taken on the line |--l of Fig. 6.

Fig. 8 is a cross section taken upon the line 8-8 of Fig. 2 and particularly showing a mandrel inserted in the work, and a holder for such mandrel.

In these views, the reference character i designates a base plate, which is centrally formed with a heavy upstanding fiat-topped rib 2. Rigidly secured on such rib by bolts 3 or the like is a bending form consisting of a heavy metal plate 4, of the size and shape to be imparted to the work. The cross-sectional form of the work may vary widely, according to its purpose, there being illustrated a length of tubular sheet metal molding 5, approximately triangular in cross section with edges spaced to provide a slot 6, co-

extensive in length with the molding. The plate 4 projects marginally to a uniform extent beyond the rib 2, and has its peripheral edge curved downwardly from the top face of the plate to conform with a correspondingly curved wall of the molding. (See Fig. 2.)

An end portion of the molding is initially insertable in a chamber 1, opening in a shoulder 7a which interrupts the edge face of the plate 4. From the outer wall of such chamber, there projects a rib 8, proportioned to pass through the slot 6, and carrying a core 9 proportioned to fit snugly within the molding. An eccentric Ill withinthe chamber 1 engages a clamping block Ii, conforming to the curved pressure-receiving wall of the molding, and is adapted to clamp said wall tightly between said block and core. The eccentric is fast on a vertical shaft l2 projecting sufliciently above the plate I for engagement by an actuating tool l3.

To apply a bending stress to the work, there is slidably inserted therein a mandrel l4, snugly conforming to the shape of the molding. Said mandrel is sufiiciently elongated to reinforce the molding and hold it to'shape for some distance in advance of the point of application of the bending stress. Integral and coextensive in length with the mandrel is a rib l5, which projects through the slot 6 and fits into a groove it of a holder i'i, being pivoted on the latter and is imposed on the work by the main section.

Swinging of the trailing section away from the forming plate beyond alignment with the main section is prevented by a forward extension II on the rib of the trailing section, adapted to seat on the rib of the main section.

The mandrel holder is mounted in a carriage adapted to be driven around the work-engaging edge of the forming plate, and. having upper and lower projections 22 and 23 adapted to respectively overlap and underlap said plate. Between said projections and facing the edge of the forming plate, is snugly inserted the mandrel holder, as best appears in Fig. 2. A lug 24 projecting from said holder, forwardly of the carriage mounts a screw 25 terminally bearing against the carriage to transmit its travel to the holder, and by adjusting said screw, the holder may be adjusted in the direction of carriage travel to accurately locate the mandrel relative to the point of application of bending stress.

To stress the molding against the forming plate, there is freely engaged with the outer face of the mandrel holder, a pin 26. slidable in the carriage to and from the mandrel. Pivoted upon the outer face of the carriage, at 21a, is an approximately vertical lever 11 having a short work arm pivoted to said pin and a long power arm pivoted to a short piston rod 26 carried by a piston 29, and axially projecting from a cylinder 30, in which this piston reciprocates. The cylinder surmounts the projection 22 and is adapted to receive compressed air (or some other energizing fluid) through a flexible tube 3| connected to the inner head of the cylinder. Said tube extends to some elevated point of supply (not shown) and has suilicient play to accommodate itself to the circuit traversed by the carriage. A valve 32 in any suitable location permits regulation of the applied fluid pressure. Thus it is seen that a powerful but fully regulable pressure is applied to hold the work against the forming plate and may be uniformly maintained throughout a bending operation, there being ample resiliency in the means applying the pressure to compensate for slight inaccuracies in either the machine or the work.

To resist the outward stress reacting on the carriage from the thrust applied to the pin 26, a pair of rollers 33, journaled on the carriage bear against the inner faces of a pair of tracks 34, rigidly secured by screws 35 to the top and bottom faces of the plate 4, adjacent to its edge. Said rollers are journaled on a pair of vertically aligned pins 36, one of which is mounted fast in each of the projections 22 and 23. Tilting of the carriage is prevented by engagement of the tracks 34 between the projections 22 and 23, and furtherby engagement of a heavy guide rail 31 between upper and lower arms. 38 and I9 integrally and outwardly projecting from the carriage. Said rail is formed at suitable intervals with outwardly and downwardly projecting lugs 40 which are boltedat 40a to the baseplate near its outer edge, and space the rail above the base plate.

For driving the carriage, a driven sprocket wheel 4| meshes with a chain 42 fixed upon the inner face of the rail 31 and continuously extending around said face. Bald sprocket wheel with its drive mechanism and a carriage for such mechanism forms a propelling unit for the firstmentioned carriage, as will presently appear. The sprocket wheel is fast on a vertical shaft 43 journaled in a pair of plates 44 and 44a respectively slidably engaging the top and bottom faces of the rail II, a short distance rearwardly of the first-mentioned carriage, and said plates are integrally connected by front and rear posts 45 and 45a. Above and below the sprocket wheel and between said plates, 9. pair of rollers 48 are fast on the shaft 43, the upper of said rollers being fitted between the rail I1 and the lower track 84 and the lower roller fitting between the rail and an annular track 41, which seats upon a shoulder 4! formed on the base plate adjacent to and surrounding the rib 2. Screws 4! or the like rigidly secure the track 41 on its seat. The plate 44 extends outwardly considerably beyond the plate 44a to mount an electric motor liil, which through grooved pulleys 5i and a V belt 5! drives a shaft 53, mounting a worm 54. The latter meshes with a worm-wheel 55 fast on the upper portion of the shaft 43, said worm and worm wheel being enclosed in a casing 56 surmounting a tubular post I51, integrally rising from the plate 44. A pair of vertically spaced arms 58 project respectively from the posts 51 and 45, and establish an articulated drive connection between the two carriages, the upper of said arms terminally engaging in a slot is formed in the projection 22 of the leading carriage and the lower of said arms engaging a bracket 40 carried by and beneath the projection 23. A pair of vertically aligned pins 8| pivotally connect the arms 58 to the leading carriage, completing an articulated drive between the two carriages allowing them to traverse a quite angular bend.

operation of the described machine, a length of molding is first slid over the sectional mandrel l4, l9, and an end portion of such length is inserted in the chamber I, so as to receive the core 8. Air is now admitted to the cylinder 30, causing the pin 28 to apply a predetermined pressure to the mandrel holder and leading mandrel section l4, to hold the inner wall of the molding against the bending form. The point of application of pressure to the leading mandrel section is sufliciently close to the rear end of said section to permit the desired bending of the molding rearwardly of said point. That portion of the leading section forward of the pressure point prevents the bending stresses from distorting the straight portion of the molding, and the trailing section ofthe mandrel safeguards the bent portion of the work from distortion.

Upon energization of the motor 50, the sprocket wheel 4| is driven, advancing along the chain 42 and carrying with it the rearward carriage. This type of drive for said carriage aifords the motor a powerful leverage, which is further augmented by the described worm and worm-wheel gearing. The forward carriage is pushed ahead of the rear one by the arms 58, and thus the molding is progressively wrapped around the bending form. The articulateddrive connection between the two carriages permits their'travel, without binding, around curves of-considerable angularity. As best appears in Fig.2, the upper track 34 sufliciently overhangs the work to prevent its upward distortion under bending stresses,

and to safeguard the bent portion of the work from upwardly escaping from the bending form. As appears in Fig. 1, the end portions of the frame formed by the bent molding overlap to some extent. This is in compensation for the resiliency of the frame, which expands sulficiently on removal from the machine to bring the ends into substantial alignment.

The annuli formed by tracks 34 and 41 and by the guide rail 31 are coaxial and parallel with the work-engaging edge of the bending form.

In removing a completed frame from the ma chine, said frame is first raised clear of the plate 4, and its ends may then be readily sprung apart to clear the forward carriage.

As compared to apparatus for manually bending molding and the like, the described machine greatly reduces labor, and considerably increases the output of bent frames.

As compared to present types of motor driven bending machines, the described machine greatly reduces complexity and cost.

The terms "rack" and gear" are used in the following claims in a sufiiciently broad sense to apply respectively to the chain and sprocket wheel which have been described and shown.

The invention is presented as including all such modifications and chansesas come within the scope of the following claims.

What I claim is:

1. A bending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a carriage, means for guiding the carriage along said edge, means for driving the carriage along said edge, a pin slidable in the carriage transversely to said edge for pressing the work against said edge, and means on the carriage for yieldably applying pressure to the pin.

2. A bending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a pair of tracks on the bending form at opposite sides of and conforming to said edge, a carriage having projections forming an opening receiving the track-mounting portion of the bending form, a pair of axially aligned rollers mounted on said projections and engaging the tracks to resist movement of the carriage from said edge, means on the carriage for pressing the work against said edge, and means for driving the carriage along said edge.

3. A bending machine comprising a bending form having a work-engaging periphery, two carriages adapted to travel along said periphery, guide rollers on the carriages, a track engaged by the guide rollers of both carriages, means on one of the carriages for driving it around said periphery, an articulated drive connection between the two carriages, and means on the other carriage for pressingthe work against said periphery.

4. A bending machine comprising a bending form having a work-engaging periphery, means for holding work against said periphery, a carriage carrying such means, a second carriage adapted to follow the first mentioned carriage, means for guiding both carriages along said periphery, an articulated drive connection between the two carriages. and drivemechanism for the following carriage, mounted thereon.

5. A machine for bending a length oflongitudinally slotted tubular molding comprising a bending form having awork-engaging periphery, a mandrel slidable in the molding to progressively press it against said periphery, a holder on which the mandrel is pivoted to conform itself to said periphery, a carriage, means for actuating the carriage along said periphery, means on the carriage for applying pressure to the holder to press the mandrel against the molding, and a member for actuating the mandrel holder with the carriage, adjustable in the direction of travel of the carriage to vary the point of application of pressure to the mandrel.

6. Abending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a carriage, means for guiding the carriage along said edge, means on the carriage for progressively conforming the work to said edge, a rack extending substantially parallel to said edge, a gear engaging the rack, a support rotatively mounting the gear, means for rotating the gear to drive the support along the rack, and a driving connection from the support to the carriage, flexible to afl'ord a relative angular movement of the carriage and support in their travel along said edge.

7. A bending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a .carriage, means for guiding the carriage along said edge, means on the carriage for progressively conforming the work to said edge, a rack extending substantially parallel to said edge, a gear engaging the rack, a shaft carrying the gear, a pair of guide rollers on the shaft one at each side of the gear, a rail carrying the rack and engaged by the rollers, a support for the shaft, a driving connection froln the support to the carriage, and means for rotating the shaft to advance the gear and its support along the rack.

8. A bending machine for elongated work comprising a bending form'having an edge of the contour to be imparted to the work, a carriage, means for guiding the carriage along said edge,

- means on the carriage for progressively conforming the work to said edge, a rack extending substantially parallel to said edge, a gear engaging the rack, a support rotatively mounting the gear, a drivingconnection from the support to the carriage, means for rotating the gear to advance its support along the rack, a rail carrying the rack, a track spaced from the rail toward the bending form, and a guide roller on the support, engaged between the rail and track.

9. A bending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a carriage, means for guiding the carriage along said edge, means on the carriage for progressively conforming the work to said edge, a chain fixed in a substantially parallel relation to said edge, a sprocket wheel operatively engaging said chain, 'a support rotatively mounting the sprocket wheel, a driving connection from the support to the carriage, and means for rotating the sprocket wheel to advance its support along the chain.

10. A bending machine for elongated work comprising a bending form having an edge of the contour to be imparted to the work, a carriage, means for guiding the carriage along said edge, means on the carriage for progressively conforming the work to said edge responsive to advance of the carriage, a rack extending substantially parallel to said edge, a gear engaging the rack, a motor driving the gear to advance it along the rack, a support for the motor and gear, and a connection from the support to the carriage for advancing the carriage with the gear.

11. A bending machine for elongated work, comprising a bending form having an edge of the contour to be imparted to the work and having opposite sides receding from such edge, a pair of tracks rigidly secured to the form at said opposite sides and conforming to the contour of said edge, a-carriage movable along the edge,

- guide members on the carriage engaging the tracks to maintain proximity of the carriage to said edge, means for driving the carriage along the edge, and means 'on the carriage for progressively conforming the work to said edge. 12 In a'bending machine for elongated work,.

a bending form having an edgeof the contour to be impartedto the work, a rail spaced from such edge and conforming to its contour,'a car- -riagemovabie along such edge, a "track rigidly carried'by the bending form'and extending along 'suchedge, means for driving the carriage along such edge, means on thecarriage for progressively conforming the work to such edge, guide means on the carriage engaging thetrack, and guide:

means on the carriage engaging the rail.

13, A bending machine asiset forth in claim 12, .:said track and rail coacting to maintain a.

proximity of the carriage to. said edge.

' 14. In a machine for bending work to an approximately annular form, a base plate, a support projecting from the central portion of such plate, a bending form rigidly mounted on the 1 support in spaced relation to such plate and having an approximately annular periphery of the contour to be imparted to the work, a rail rigidly carried by the base plate and forming an annulus, substantially conforming in contour and spaced outwardly from said periphery, a carriage engaged with the rail for travel along said periphery, means for driving the carriage, and means on the carriage for progressively conforming the work to said periphery. V

15. A bending machine for elongated work comprising abending form having an edge of the contour to be imparted to the work, a rack extending parallel to said edge, means connecting the rack and form as a unit, a member adjacent to said edge for pressing the work against said edge, means for applying pressure to said member, a mounting for said member and means positioned in a substantially fixed proximity to said bending form having an edge of the contour to.

be imparted to the work, a carriage having projections at opposite sides of said edge, a mandrel inserted in the work, a holder for the mandrel mounted on the carriage between its said pro-- jectlons, a. drivingconnection from the holder to' the mandrel passing through said slot, means on the carriage for generating pressure, a lever pivotal on the carriage for applying such pressure to the mandrel holder -and :toward the work,

means forguiding the carriage along said edge,

" and means for driving-the carriage along said edge.

. 17, A bending machine I for elongated work comprising a bending form having an edge of the eonto'ur'to be impartedto'the work, a. shoulder interrupting. said edge and a chamber opening 75 'insuch shoulder'in alignment with a straight said end portion therein during a bending operation, and means having a fixed operating relation to' the cam for rotating the cam.

19. A bending machine comprising a bending form having a'work-engaging periphery, a rail 'carriage for applying bending pressure to the vwork, coacting means on the carriage and the peripheral portion of, the, form for holding the carria e in a substantially definite proximity to said periphery, and means reacting with the rail to advance thecarriage.

b 20. A bending machine as set forth in claim 19, the last-mentioned means including a motor connected'to the carriage and movable therewith along said periphery.

21. A machine for bending a length of longitudinally slotted tubular molding comprising a bending form having a work-engaging periphery, a mandrel slidable in the molding, a mandrel holder, a member adapted to pass through the molding slot and pivoting the mandrel on the holder, whereby the mandrel may angularly conform itself'to said periphery, an applicator effective on the holder to press the mandrel against the molding, means for relatively shifting the form and applicator to progressively impose applicator pressure on the molding, and means for maintaining the working relation of the applicator and holder, adjustable to vary such relation.

22. In a machine for bending a length of longitudinally slotted tubular molding, a bending form having a work-engaging periphery a mandrel slidable in the molding, a mandrel holder, an applicator carrying the holder and effective on the holder to press the mandrel against the molding, the applicator having a chamber wherein the holder is fitted, a pressure transmitting connection between the holder and mandrel, said connection being established through the slot of the molding, and means for relativelyshifting the form and applicator to progressively impose applicator pressure on the molding.

23. A bending machine comprising a bending form having an edge of the contour to be imparted to the work, mechanical means for wrapping ,an elongated piece of work around said edge,

the form having a chamber in part aligned with a portion of said edge, whereby an end portion of the work may be entered in the chamber preliminary to a bending operation, a clamping element within such chamber effective upon said end portion of'the workto hold it fixed, actuating means for the clamping element carried by the form, 'said means beingeifective to maintain a clamping pressure throughout an operation of the wrapping means, and a .core member carried by the form within said chamber and engageable within tubular work as suchwork is entered in the chamher and preventing collapse of such work under pressure of the clamping element.

,24. Apparatus for bending straight lengths of metallic stock into curvilinear formations, comprising a bending Iorm having two substantially parallel elongated edges, oi. desired but irregular curvilinear shape, one of such edges facing inwardl-y and the other outwardly, a traveling bender embracing a portion of the torm so as to be movable along'saidedges, a sprocket chain immovably affixed to and extending along said inwardly lacing edge, and conforming to the curvature of such edge, the cross pins of said chain constituting equl-spaced rack teeth adapted to conform themselves to the curvature o! the form without alteration -01 pitch through all variations of the irregular pitch line required to follow said curvature, a drive sprocket connected to saidtraveling bender to mesh with said sprocket chain, means to rotate said sprocket, and bending means carried by said traveling bender to oppose and cooperate with .said outwardly facing edge of the form, the stock to be worked between said bending means and isaidicutwardly lacing edge.

GEORGE R. GOIN'. 

